Fav, affordable, cylinder measuring tools

[demolitionman]

I do a fair amount of basic top end rebuilding on my 2 stroke dirtbikes as well as for a few other friends, and have used a god knows what brand cylinder bore T then I'd take a vernier digital caliper to check it per book specs and order a certain lettered oem piston to rough match the amount cylinder wear. I'm certain other types of inside bore measuring devices coupled with a cylinder OD measuring tool would be a far better way although what I've done seems to have been working fine since I started racing 2strokes way back in highschool as I've racked up a mess of racing seasons on my yz250 motors with little to no major problems.

So, at the risk of sounding like a cheap ***, do any of you (probably small engine tech types) have any cylinder measurement tools that you reccomend that don't break the bank. right now I think all I'm looking for is a new inside diameter T type caliper and a outside diameter measuring device to both check the "T's" spec and the OD of the cylinder, so I can better match my cylinder piston sizes and ring end gaps. Thanks.


FYI, note I'm talking 2 strokes here so there's a lot of exhaust holes in the cylinder to work around when measuring.

 

[Packard V8]

Watch eBay for deals on a Chicom dial bore gauge set in the 1"-6" range. They sometimes sell amazingly cheaply and will be more accurate than what you're doing now.

jack vines

 

[royesses]

1.4 to 6" Dial bore gauge $79.99:
http://www.littlemachineshop.com/products/product_view.php?ProductID=3448&category=1070498684

I just purchased one a couple of weeks ago. Igaging is some decent measuring tools.

Enco Import Micrometer set - .0001 reading:
https://www.use-enco.com/CGI/INPDFF?PMKANO=400&PMPAGE=43&PARTPG=INLMPA&PMCTLG=01

0-3" or 0-6" are pretty cheap. I've checked these out and they are accurate. I have Mitutoyo but they are expensive. I have a set of SPI electronic mics also that are about $60 to $80 each when Enco puts them on sale. Nice because you can instantly switch between metric and inch.

 

[martin666]

Watch ebay for Central Tools dial bore gauge, telescoping gauges and the appropriate mic. I picked up 2 dial bore gauges last year for under $50 each. Decent tools USA made and plenty good enough for your needs

 

[Monkey Milk]

I believe he's using telescoping gauges. He calls them "T" but he checks them with a caliper.

You can use telescoping gauges if you use a micrometer. You will have to take several point measurements but a dial bore gauge is better suited this like other has mentioned.

 

[VoodooCLD]

I find "T" gauges. Also called snap gauges, or telescoping gauges, are really inaccurate.
You'd be much better served with a bore gauge like this fowler. I've used this exact same set and it works well.

Bore Gauge
http://www.amazon.com/dp/B000XQ2T1E/?tag=atomicindus08-20

Then you'd also use a micrometer. This set might be overkill, as it goes from 0"-6". You could always buy a single one that has a range closer to your piston size.

Micrometer set
http://www.amazon.com/dp/B00B5KQ62K/?tag=atomicindus08-20

I rebuilt my my old 96 YZ250 with these tools, and a freshly replated nikosil cylinder.
Also did a Mopar 440 big block engine.

 

[JoeFin]

This is what I use

found on eboner for about $50

 

[LXCam]

I find "T" gauges. Also called snap gauges, or telescoping gauges, are really inaccurate.
You'd be much better served with a bore gauge like this fowler. I've used this exact same set and it works well.

Bore Gauge
http://www.amazon.com/dp/B000XQ2T1E/?tag=atomicindus08-20

Then you'd also use a micrometer. This set might be overkill, as it goes from 0"-6". You could always buy a single one that has a range closer to your piston size.

Micrometer set
http://www.amazon.com/dp/B00B5KQ62K/?tag=atomicindus08-20

I rebuilt my my old 96 YZ250 with these tools, and a freshly replated nikosil cylinder.
Also did a Mopar 440 big block engine.

That's the same dial bore gauge I have. Between this and a couple micrometers you'd be much better off. If you watch for sales at Enco (use-enco) you'll find sales at 25% off which makes this unit pretty reasonable.

Matter of fact, Enco has a 15% off that ends tonight. Use this code: JANSALE

 

[Kevin54]

I find "T" gauges. Also called snap gauges, or telescoping gauges, are really inaccurate.You'd be much better served with a bore gauge like this fowler. I've used this exact same set and it works well.

Bore Gauge
http://www.amazon.com/dp/B000XQ2T1E/?tag=atomicindus08-20

Then you'd also use a micrometer. This set might be overkill, as it goes from 0"-6". You could always buy a single one that has a range closer to your piston size.

Micrometer set
http://www.amazon.com/dp/B00B5KQ62K/?tag=atomicindus08-20

I rebuilt my my old 96 YZ250 with these tools, and a freshly replated nikosil cylinder.
Also did a Mopar 440 big block engine.

Why is a telescoping gage inaccurate?

 

[MBfreak]

JoeFin
The three point gauge you show is really the best tool that an amateur or small shop can use.

Best regards

Olaq

 

[Ohmthis]

Kevin, I believe that statement was made because they haven't taken the time to properly learn to use the telescoping gauges. They do take time and "feel" to use them with repeatable, accurate results. Also some people will close the micrometer too tight and throw off the results. Practice and you can use them very well.

 

[chillrich]

Re: telescoping gauges
I'm sure it is possible but it is very difficult for the home mechanic to develop the feel to get repeatable measurements with telescopic gauges when measuring tolerances less than 0.05mm as we see on nikasil coated cylinders. This requires experience and feel even with a dial bore gauge.

I want a point gauge now ;-). Still need dial bore for out of round measurements.

 

[larry_g]

On any system you choose you will have to have a standard to check your measuring tool against.

lg
no neat sig line

 

[purplezr2]

I have a fowler at home and a mituyoto at work. I set them to nominal bore size and measure

 

[VoodooCLD]

The T gauges are susceptible to misreadings as its takes some practice and feel to use them properly. You need to set the tension on the lock just right, and then sweet the gauge up or down to allow the plunger to compress to the proper dimension. If you just stick it in there and release the lock you could get a misreading due to the plungers not being perfectly perpendicular and centered in the bore.

The bore gauge uses this same principle, however you get real time readings as you sweep the gauge back and forth. It also benefits from having 3 points of contact as opposed to 2. This helps keeps you centered in the bore.

If you want to check piston to bore clearance you can measure the piston with a micrometer and lock it at that dimension. Then use the interchangeable anvils and adjustable dial on the bore gauge to set the gauge up to read zero when swept between the micrometers anvils. Then when you sweep the calibrated bore gauge through the bore, it will give you a difference reading from that of the micrometer/piston.

The bore gauge is not a direct reading measuring tool, its a comparative device. You're comparing the differential reading on the bore gauge from that of the micrometer.

 

[justanengineer]

If you want to check piston to bore clearance you can measure the piston with a micrometer.....

You can measure them with a mic, but there's no point as your measurement wont mean dink. ICE pistons for more than half a century have been non-uniformly oval and tapered.

For the OP's intended use (measuring the bore) a bore gauge is basically useless. I'd suggest either sticking with snap gauges or getting a 2 point inside mic set. If he wants a bore gauge, the proper one to use rebuilding an engine is a 2 point.

 

[Packard V8]

On any system you choose you will have to have a standard to check your measuring tool against.

Dial bore gauges require a setting tool. Each time we use our Sunnen, it's verified against the setting tool, which is verified against a standard.

The bore gauge is not a direct reading measuring tool, its a comparative device. You're comparing the differential reading on the bore gauge from that of the micrometer.

For true, as above. The dial bore gauge shows how many tenths +/- the bore diameter differs from the desired and pre-set standard.

I'd take a vernier digital caliper to check it per book specs and order a certain lettered oem piston to rough match the amount cylinder wear.

For the OP's intended use (measuring the bore) a bore gauge is basically useless. I'd suggest either sticking with snap gauges or getting a 2 point inside mic set.

Can you explain that in more detail? We use the dial bore gauge on every engine we bore and hone. The OP knows the bore diameter and is measuring wear in fractions of a mm from that known and calculating which oversize piston to order to get back to the desired piston-to-bore clearance.

jack vines

 

[lilxtra]

Goodson is what I used for building high performance engines at my shop

 

[justanengineer]

Can you explain that in more detail. We use the dial bore gauge on every engine we bore and hone.

If the OP's only need is to measure the bore diameter to order a replacement piston an inside mic or snap gauge is much faster (no setup), much less expensive, and just as accurate as a bore gauge. Maybe I'm misunderstanding thanks to the bourbon, but that was the use mentioned.

OTOH, if he's wanting to "check" his machinist's work or overbore/hone DIY he's going to very quickly run into the same problem as with snap gauges - expensive, accurate, special tools and a decent amount of skill are needed to measure bore cylindricity, ovality, and crank offset. I've known many professional machinist's who couldnt do it properly, nvm a hobbyist.

 

[Ohmthis]

I'll argue that the snap gauge is faster, less expensive yes. After setting up the bore gauge (let's say 5 min, tops) you can quickly check the bore top to bottom. With the snap gauge you have to pull it out and measure it. For accuracy the same place in the bore should be remeasured at least twice. That would be roughly 18 different set the gauge, pull it out, and measure.
An inside micrometer is probably the best tool for him if speed, accuracy, ease of use, and expense are all added to the equation.

 

[Packard V8]

If the snap gauge is all that's needed, why does every professional shop I know use the dial bore gauge?

jack vines

 

[rustytruck66]

I find "T" gauges. Also called snap gauges, or telescoping gauges, are really inaccurate.
You'd be much better served with a bore gauge like this fowler. I've used this exact same set and it works well.

Bore Gauge
http://www.amazon.com/dp/B000XQ2T1E/?tag=atomicindus08-20

Then you'd also use a micrometer. This set might be overkill, as it goes from 0"-6". You could always buy a single one that has a range closer to your piston size.

Micrometer set
http://www.amazon.com/dp/B00B5KQ62K/?tag=atomicindus08-20

I rebuilt my my old 96 YZ250 with these tools, and a freshly replated nikosil cylinder.
Also did a Mopar 440 big block engine.

I believe he's using telescoping gauges. He calls them "T" but he checks them with a caliper.

You can use telescoping gauges if you use a micrometer. You will have to take several point measurements but a dial bore gauge is better suited this like other has mentioned.

Telescoping gages are plenty accurate if you know how to use them right. I use them almost on a daily basis at work and am comfortable measuring + or - .0005" with them... it's all about the feel. If you use these to measure a cylinder bore, be sure to take several measurements at various angles to determine out of roundness, taking a single measurement at one location won't tell you anything...

Sent from my SCH-I545 using Tapatalk

 

[ttpete]

The most accurate way to calibrate a dial bore gauge is to use one of these along with a set of jo-blocks.

http://www.amazon.com/dp/B007QV1GB8/?tag=atomicindus08-20

When we were racing a Yamaha TD3 250, it used chrome plated aluminum cylinder bores, and we had a shop that would strip and re-chrome them, then hone to size. We had a ring gauge made to the nominal bore diameter, and would send it along with instructions to hone to gauge.

 

[Packard V8]

This is what we use on our Sunnen.

jack vines